President Barack Obama is the 17th president to be inaugurated for a second time.
Some of South Dakota's top politicians were at the ceremonial swearing-in Monday and joined by an estimated 800,000 people.
Republican South Dakota Senator John Thune could be seen arriving for the ceremonies with Democratic Senator John Kerry, who has been nominated as the next Secretary of State.
The office for Democratic Senator Tim Johnson told KELOLAND News Monday morning that South Dakota's senior Senator was in attendance at the inauguration.
There is no word yet on whether Representative Kristi Noem is attending Monday's events.
We will talk with South Dakota's Congressional delegation about their participation in the 57th inauguration later today on KELOLAND News.